One conventional system known in the art includes an ink cartridge, and an inkjet recording device. The inkjet recording device includes an attachment portion. The ink cartridge can be attached to and detached from the attachment portion.
One such inkjet recording device has an inkjet head, and a hollow supply needle that is inserted into the ink cartridge when the ink cartridge is attached to the attachment portion. Ink stored in the ink cartridge is supplied to the inkjet head through the supply needle. A valve and spring may be provided in the supply needle for preventing ink from leaking out of an interior of the supply needle (see Japanese Patent Application Publication No. 2006-95817, for example). The spring urges the valve toward a closed position in which the valve closes an opening formed in the supply needle. When the ink cartridge is attached to the attachment portion, the valve is moved against the urging force of the spring to an open position and is maintained in this open position. A valve and spring may also be provided in the ink cartridge for preventing ink from leaking out of the cartridge. Through contact with parts of the attachment portion, the ink cartridge is maintained at a prescribed position in the attachment portion against the urging force of the spring. In a state in which the ink cartridge is maintained in this prescribed position in the attachment portion, each of the valves is also maintained in its open position. The ink cartridge may further be provided with an IC board or the like that stores information related to the ink cartridge, such as information on the residual quantity of ink in the ink cartridge.